Types of Smoke Alarms

There are 2 basic types of smoke alarms: ionization and photoelectric. Both are effective at detecting smoke, yet each has a unique detecting system.

Ionization
Ionization technology is generally more sensitive than photoelectric technology at detecting small particles which tend to be produced in greater amounts by flaming fires, which consume combustible materials rapidly and spread quickly. Sources of these fires may include paper burning in a wastebasket, or a grease fire in the kitchen.

Look for this symbol on the label:

Photoelectric
Photoelectric technology is generally more sensitive than ionization technology at detecting large particles, which tend to be produced in greater amounts by smoldering fires, which may smolder for hours before bursting into flame. Sources of these fires may include cigarettes burning in couches or bedding. Each type of detector also comes as AC-operated smoke alarms or battery-operated smoke alarms. Some AC alarms even come with a battery back-up system. Additional options can include an escape light, silencing button, or remote control mute feature.

Look for this symbol on the label:

Combination Detectors
Combination Ionization/Photoelectric detectors and alarms utilize both technologies within 1 device. The combination device may be the best for certain locations.